Solar heated fluid recirculation device

ABSTRACT

A system for the sequential application of thermal energy subterranean of a structure The system includes a solar thermal collector, fluid for passing through the solar thermal collector for receiving thermal energy therefrom and a pump for passing the fluid through the solar thermal collector and selectively into a plurality of heat exchangers. Each of the heat exchangers is positioned at different levels subterranean and beneath the structure whereby the fluid is selectively introduced to one of the plurality of heat exchangers depending upon a predetermined time of year.

TECHNICAL FIELD

The present invention is directed to a system for selectively introducing thermal energy to a structure, such as a residential or commercial building making use of thermal energy derived from a solar thermal collector. Thermal energy developed through the practice of the present invention is selectively introduced to the structure subterraniously in order to enable the introduction of heat energy at floor level making optimal use of such energy.

BACKGROUND OF THE INVENTION

Solar thermal collectors, although providing a clean source of thermal energy not dependent upon the burning of petroleum based fuels is attractive conceptually, its adoption has not been universal. Inherent problems exist associated with the storage of heat for use at a later time. Large volumes of heated fluids are necessary and the cost of providing storage devices of adequate size has, in the past, represented a clear limitation to such wide scale adoption.

There have been instances where heated fluids have been subject to in-ground storage where the ground itself has been used for heat or cold storage For example, reference is made to U.S. Pat. No. 3,262,493 teaching the use of ducts buried directly into the ground for such purpose The ground located about the ducts is used for heat or cold storage. However, the high cost of duct work, which is expensive to install and to maintain, has proven to be a limitation.

U.S. Pat. No. 2,680,565 teaches the use of rock as storage media employing a separate chamber inside of a room or bin within a home heated by such rock. U.S. Pat. Nos. 3,369,541 and 3,412,728 employ solid heat storage media teaching the use of stones or sand within chambers or bins for storage. None of these systems, however, have proven to be particularly useful and wide scale adoption of them has been elusive.

There has been, prior to the present invention, no practical way to transfer thermal energy from a subterranean location to a structure in a manner that is reflective of the seasons of the year. Specifically, an ideal such system would apply more thermal energy to the structure in the winter months than in the summer months and would do so without the need for extensive redirection or sophisticated hardware applied to the task.

It is thus an object of the present invention to provide a system which is capable of overcoming the drawbacks identified above.

It is yet a further object of the present invention to provide a system for the sequential application of thermal energy subterranean of a structure in a manner which is simple to operate, uncomplicated and, ideally, automated to provide the sought after results and to do so in a manner dependent upon the time of year.

These and further objects will be more readily apparent when considering the following disclosure and appended claims.

SUMMARY OF THE INVENTION

The present invention involves a system for the sequential application of thermal energy subterranean or a structure, said system comprising a solar thermal collector, a fluid for passing through said solar thermal collector for receiving thermal energy therefrom, a pump for passing said fluid through said solar thermal collector and selectively into a plurality of heat exchangers, each of said heat exchangers being positioned at different levels subterranean and beneath said structure, whereby said fluid is selectively introduced to one of said plurality of heat exchangers depending upon a predetermined time of the year.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A is a side plan view of a structure having a trench dug for installation of the present invention.

FIG. 1B is a side plan view showing the use of an auger to create opening for installing heat exchangers per the present invention.

FIG. 2 is a side plan view of the structure of FIG. 1 embodying the present invention

FIG. 3 is a side plan view of a structure embodying a preferred embodiment of the present invention

FIG. 4 is a schematic illustration of a valve used to selectively direct heated fluid to various heat exchangers per the present invention.

FIG. 5 is a crossectional view of a heat exchanger used in practicing the present invention.

FIG. 6 is a schematic depiction of a timer/controller for use herein.

DETAILED DESCRIPTION OF THE INVENTION

Novel features which are characteristic of the invention, as to the organization and method of operation, together with further objects and advantages thereof will be better understood from the following description considered in connection with the accompanying drawings, in which preferred embodiments of the invention are illustrated by way of example. It is to be expressly understood, however, that the drawings are for illustration description only and are not intended as definitions of the limits of the invention The various features of novelty which characterize the invention are recited with particularity in the claims.

There has been broadly outlined more important features of the invention in the summary above in order that the detailed description which follows may be better understood, and in order that the present contribution to the art may be appreciated There are, of course, additional features of the invention that will be described hereinafter and would perform additional subject matter of the claims appended hereto Those skilled in the art will appreciate that the conception upon which the disclosure is based readily may be utilized as a basis for the designing of other structures, methods and systems for carrying the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent construction insofar as they do not depart from the spirit and scope of the present invention.

Noting that heat transfer from higher to lower concentration, by conduction from solid to solid is much more efficient than by air to solid, it is generally appreciated that the addition of thermal energy to a structure, be it residential or commercial building can be most effectively achieved by providing such thermal energy through the floor and furnishings When heat is added to the ground for a short period of time, only a few inches of the surrounding earth is significantly heated. On the other hand, when the duration of introduction is weeks or months, the accumulated heat will migrate many feet from the source of the heat, through the ground, raising the temperature significantly.

Reference is first made to FIG. 1 showing structure 10 residing on earth 5. Flooring 8 is contiguous with earth 5. In the implementation of the present invention, trench 24 is created adjacent to structure 10 through the use of a backhoe or similar commonly employed trench digging implement. Once trench 24 is created, the next step in the process is illustrated by reference to FIG. 1B.

In creating the appropriate openings to install heat exchangers in carrying out the present invention, auger 3 is placed within trench 24 and helical bit shown alternatively as elements 3A, 3B and 3C penetrate ground 5 for establishing generally cylindrical openings beneath structure 10. In the illustration of the present, three such openings are created although the exact number of openings and, consequently, the number of heat exchangers established beneath dwelling 10 can be a matter of design choice, three such openings being created in this illustration for the purpose of providing a full and clear understanding of the present invention.

With the above considerations in mind, reference next is made to FIG. 2 showing the basics of the system of the present invention. Specifically, structure 10 is shown residing upon earth 5. Structure 10 is shown as having sloping roof 9 although such structures can oftentimes have flat roofs and it is contemplated that virtually any roof configuration can be employed in practicing the present invention

Due to concerns about possible anthropogenic global warming stemming from the burning of fossil fuels, solar water heating systems have been widely used Adaptation of solar heating to homes and buildings is an increasingly attractive proposition considering the price volatility and international political conflicts driven by the depleting supply of easy to obtain oil.

A suitable solar heating system 20 is shown installed upon roof 9 preferably positioned to capture the maximum amount of solar energy by facing the solar thermal array 22 appropriately to maximize solar exposure and minimize shading from trees and adjacent structures. Solar array 22 can also be supported on poles and other structures unrelated to the roofs of buildings. A suitable system for use herein is offered by Apricus® consisting of an array of evacuated heat tubes mounted in a header 23. Solar radiation is absorbed by the heat tubes and converted to heat. A low voltage, low volume, electric, recirculation pump 58 which may be AC or DC powered by an attached photovoltaic panel (not shown) pumps the fluid into the header where it absorbs the heat as it flows through. From the header outlet the fluid will travel through a non-metallic fluid line. A suitable product for use herein is known by those familiar with the art as PEX tubing. The fluid, depending on type, may pass through an air separator 12 and/or may be connected to an expansion tank 11 to protect the system from bursting. Solar array 22 can be appropriately positioned upon roof 9 employing supporting hardware 21 shown schematically in FIG. 2. It is proposed that such installations are quite commonplace and the appropriate hardware and positioning of panel 22 is something commonly available to those in this field.

Under normal circumstances, fluid circulated from header 23 through air separator 12 and expansion tank 11 would be fed directly into the appropriate piping within structure 10 for providing hot fluid both to heat the dwelling. When the fluid is water, it can be used for such things as dishwashing, bathing, showering and the like However, the present invention contemplates a much differ ent use of this heated fluid as explained below.

It has been fundamentally recognized herein that creative use can be made of the solar energy imparted to fluids by circulating the fluid, be it water or an alternative medium, through a plurality of heat exchangers 41, 42 and 43 fit within holes created by auger 3 in the form of elongated tubes located subterranean of structure 10 within earth 5 Heated fluid is circulated via fluid lines 14 and 16 to valve 15, valve 15 directing the fluid imparted with thermal energy from header 23 selectively and depending upon the time of year.

The structural details of a typical heat exchanger for use herein is shown in FIG. 5 Specifically, heat exchanger 41 is shown having inlet 160 for the receipt of heated fluid selectively from valve 15. The same heated fluid can pass from heat exchanger 41 through element 161, the heated fluid being prevented from passing beyond opening 165 through the use of barrier 3. Alternatively, insulation 163 can be outfitted within heat exchanger 41 as shown to prevent heated fluid from entering into the space occupied by the lower half of the exchanger.

As depicted in FIG. 1B, when installing the system of the present invention, one would generally create trench 24 enabling one to drill appropriate subterranean openings diagonal or perpendicular thereto for installing a series of heat exchangers, depicted in FIG. 2 as first, second and third heat exchanger tubes 41, 42 and 43, respectively. Each heat exchanger, 41, 42 and 43 are fed heated fluid via fluid line 17, 18 and 19, respectively, from valve 15 said fluid being recirculated from the heat exchangers back through valve 15 via fluid lines 17 a, 18 a and 19 a.

The schematic details of valve 15 is shown in FIG. 4. Specifically, heated fluid from header 23 is introduced into valve 15 through line 14. It is then distributed to heat exchanger 43 via tube 19, or to heat exchanger 42 via tube 18, or to heat exchanger 41 via tube 17. The selective passage of heated fluid from header 23 to the various heat exchangers can also be carried out manually via valves 171, 172 and 173 or actuated by an appropriate solenoid. Recirculated heated fluid from heat exchanger 43 is returned to valve 15 via tube 19 a while, similarly, fluid returned to valve 15 from heat exchanger 42 is carried out via tube 18 a and heated fluid returned to valve 15 from heat exchanger 41 is carried out via tube 17 a. Finally, this heated fluid is returned to recirculation pump 58 through tube 16.

It is noted that the heat exchanges are in the form of elongated tubes although virtually any physical shape can be employed while remaining within the spirit and scope of the present invention. Further, it is noted that first heat exchanger 41 is located proximate floor 8 of structure 10 while third heat exchanger 43 is located relatively distant from floor 8 and second heat exchanger 42 is located between first and second elongated tubes 41 and 43.

It is an important aspect of the present invention that heated fluid be introduced to the appropriate heat exchanger beneath structure 10 depending upon environmental conditions which are present at the time. In turning to FIG. 6, it is proposed that an annual timer 50, which can be preset or programmable being powered from source 51 provide a signal to valve 15 directing it to appropriately recirculate heated fluid either through lines 17 a, 18 a or 19 a for selectively introducing such fluid to one of the plurality of heat exchangers beneath floor 8 of structure 10. If this process is to be carried out in the northern hemisphere and in a preprogrammed and automated fashion, though it could easily be accomplished manually, it is proposed that third elongated tube 43 receive heated fluid in the months of April through July when it is anticipated that the temperatures would be at their highest in the vicinity of structure 10. In keeping with this theme, second elongated tube 42 would receive heated fluid in the months of August through November, adding to the heat deposited in the prior phase. First tube 41 would receive heated fluid in the months of December through March, adding still more heat to that which was deposited in the previous two phases, and arriving at structure 10 just when it is anticipated that environmental temperatures would be lowest

In quantifying this matter further, it is proposed that third elongated tube 43 be positioned between approximately 15 to 20 feet beneath floor 8, that second elongated tube 42 be positioned between approximately 5 and 10 feet beneath floor 8 while first elongated tube 41 be positioned substantially adjacent to floor 8 of structure 10.

It is proposed that controller 50 can be overridden by signal generator 55 receiving instructions from the actuation of lever 57 of switch 56. Thus, if one was to experience an unusually cold spell in the spring or summer months or particularly warm spell in the winter months, heated fluid could be appropriately directed to one of the heat exchangers located beneath structure 10 appropriately.

The present invention is intended to take advantage of the recognition that soil is not a good heat conductor, nor is it a good insulator. It has a fairly good heat capacity. Specifically, over a period of a few hours, heat does not move very far into a layer of earth. Over a period of a few days or weeks, or even months, heat may move a number of feet into soil, but at distances of 10 or 20 feet or more, many months are needed before significant temperature changes are felt. Thus, during the summer months when it is not crucial that significant amounts of thermal energy are received within structure 10, that elongated tube 43 be the recipient of thermal energy created by solar panel 22 while in the winter months when heat is most necessary, that the heated fluid be directed to elongated tube 41.

In order to maximize the usefulness of the present invention, reference is made to FIG. 3. In this regard, it is noted that heat exchangers 41, 42 and 43 can benefit by being isolated from earth 4 not located directly beneath dwelling 10. Thus, heat exchangers 41, 42 and 43 can be thermally isolated from earth 4 as well as being protected from the intrusion of ground water by creating a trench and installing barrier 45 about the perimeter of dwelling 10. This barrier can be in the form of simple polyethylene sheeting material which can be installed contemporaneously with the construction of dwelling 10 or can be considered an add on adjunct when the present invention is installed

The above disclosure is sufficient to enable one of ordinary skill in the art to practice the invention, and provides the best mode of practicing the invention presently contemplated by the inventor. While there is provided herein a full and complete disclosure of the preferred embodiments of the invention, it is not desired to limit the invention to the exact construction, dimensions, relationships or operations as described. Various modifications, alternative constructions, changes and equivalents will readily occur to those skilled in the art and may be employed as suitable, without departing from the true spirit and scope of the invention Such changes might involve alternative materials, components, structural arrangements, sizes, shapes, forms, functions, operational features and the like.

Therefore, the above description and illustration should not be considered as limiting the scope of the invention, which is defined by the appended claims 

1. A system for the sequential application of thermal energy subterranean of a structure, said system comprising a solar thermal collector, a fluid for passing through said solar thermal collector for receiving thermal energy therefrom, a pump for passing said fluid through said solar thermal collector and selectively into a plurality of heat exchangers, each of said heat exchangers being positioned at different levels subterranean and beneath said structure, whereby said fluid is selectively introduced into one of said plurality of heat exchangers depending upon a predetermined time of the year.
 2. The system of claim 1 comprising three of said heat exchangers in the form of elongated tubes.
 3. The system of claim 2 wherein said elongated tubes are caused to extend diagonally to or parallel to and beneath the floor of said structure, a first of said elongated tubes being located relatively proximate said structure, a third of said elongated tubes being located relatively distant said structure and a second of said elongated tubes being located between said first and third elongated tubes.
 4. The system of claim 3 wherein said first elongated tube is caused to receive said fluid in the months of December through March.
 5. The system of claim 3 wherein said second elongated tube is caused to receive said fluid in the months of August through November.
 6. The system of claim 3 wherein said third elongated tube is caused to receive said fluid in the months of April through July.
 7. The system of claim 1 further comprising a fluid barrier extending below the periphery of said structure and exterior to said plurality of heat exchangers.
 8. The system of claim 1 wherein said solar thermal collector is located on the roof of said structure.
 9. The system of claim 3 wherein said third elongated tube is positioned between approximately 15-20 feet beneath the floor of said structure.
 10. The system of claim 3 wherein said second elongated tube is positioned between approximately 5-10 feet beneath the floor of said structure.
 11. The system of claim 3 wherein said first elongated tube is positioned substantially adjacent to the floor of said structure
 12. The system of claim 1 further comprising a valve for selectively directing said fluid to each of said heat exchangers.
 13. The system of claim 12 wherein said valve is programmed to direct said fluid selectively to each of said heat exchangers depending upon the time of year.
 14. A method for selectively introducing thermal energy subterranean of a structure, said method comprising providing a solar thermal collector for receiving thermal energy therefrom, passing said fluid through said solar thermal collector and selectively into a plurality of heat exchangers, positioning said heat exchangers at different levels subterranean and beneath said structure and selectively introducing into one of said plurality of heat exchangers said fluid depending upon a predetermined time of the year.
 15. The method of claim 14 whereby said heat exchangers, in the form of elongated tubes, are extended diagonally to or parallel to and beneath the floor of said structure, locating the first of said elongated tubes proximate said structure, locating the third of said elongated tubes relatively distant to said structure and a second of said third elongated tubes being located between said first and said elongated tubes.
 16. The method of 15 wherein said fluid is passed within said first elongated tube in the months of December through March.
 17. The method of claim 15 wherein said fluid is caused to pass within said second elongated tube in the months of August through November
 18. The method of claim 15 wherein said fluid is caused to pass within said third elongated tube in the months of April through July.
 19. The method of claim 14 further applying a fluid barrier extending below the periphery of said structure and exterior to said plurality of heat exchangers.
 20. The method of claim 15 comprising the positioning of said third elongated tube is positioned between approximately 15-20 feet beneath the floor of said structure.
 21. The method of claim 15 comprising the positioning of said second elongated tube is positioned between approximately 5-10 feet beneath the floor of said structure.
 22. The method of claim 15 comprising the positioning of said first elongated tube is positioned substantially adjacent to the floor of said structure.
 23. The method of claim 14 whereby a valve is provided for selectively directing said fluid to each of said heat exchangers.
 24. The method of claim 23 wherein said valve is programmed to direct said fluid selectively to each of said heat exchangers depending upon the time of the year. 